Plasmon losses in Al-Mg alloys

The plasmon losses of the α, β, γ and δ phases of the Al-Mg alloy system have been measured by combined electron microscopy and velocity analysis. This technique, together with a detailed knowledge of the loss spectra of alloys, permits a microanalysis of precipitates too small and weakly dispersed to be identified by conventional diffraction methods. A comparison of the experimental and theoretical values of the losses is given. The energy widths of the losses measured at half maximum intensity were found to be independent of alloy composition. This result is in contradiction to those of previous authors and a reason is suggested for this discrepancy.